Not all fungi are good for plants or bees, or even people.

Anyone who has experienced mold outbreaks, wilting vegetable plants, or devastated flowers knows the destructive power of fungi. Washington State University researchers and Extension outreach specialists lead the fight against some these sinister fungi.

 

Fighting fungus in apples, pears under storage

Molds and fungi can wreck a good apple or pear.

Just ask Achour Amiri, assistant professor and researcher at the Washington State University Tree Fruit Research & Extension Center in Wenatchee. He specializes in diseases that spoil tree fruit and he can be found working in packing rooms and warehouses throughout central Washington.

“Winter is when pathogens start to show up in storage,” Amiri says.

“I visit packers to understand their problems. Do they see unusual decay rates or decay that they’re not used to? I try to find out why and deliver solutions.”

Packers have only a few fungicides to work with, so Amiri and his team tests Washington fruit to find possible geographic variability in pathogens across the state. A clear picture of pathogen populations could help fruit packers make science-based decisions on what and when to spray.

Read more about Amiri and his work (Story by Seth Truscott, College of Agricultural, Human & Natural Resource Sciences-CAHNRS)

 

Plants vs. white mold rot

An insight into how the fungi that causes white mold rot avoids plant defenses could lead to a new tool to combat a pathogen that causes billions of dollars of crop loss worldwide.

A team led by US Department of Agriculture’s Agricultural Research Service and Washington State University researchers found that the Sclerotinia sclerotiorum fungus uses a protein, called SsPINE1, to bypass natural plant defenses and cause extensive rot in hundreds of broad leaf plant varieties.

Sclerotinia causes stem rot on more than 600 plant species, including peas, lentils, canola, potatoes, soybeans, and many other broad leaf crops,” said Weidong Chen, corresponding author on the paper, adjunct professor at WSU and plant pathologist with the USDA-ARS.

Read more about plant defenses against white mold rot (Story by Scott Weybright, CAHNRS)

 

Ugly fungal disease in peonies

Pacific Northwest farmers have found success growing peonies for a thriving global market. But a devastating fungus called Botrytis is limiting market growth and profits for Northwest farmers.

The peony is a symbol of good fortune and happy marriage and has been a beloved centerpiece of floral arrangements and wedding bouquets for hundreds of years.

Stippling the peony’s emerald leaves with unsightly blotches of brown and purple, Botrytis can ruin up to half of growers’ crops long before they’re ready to sell.

What’s worse, the fungus can strike invisibly, turning a shipped box of seemingly perfect flowers into a brown-streaked mess, leading to upset customers and cancelled payments.

“Diseases caused by Botrytis are the peony’s number one health problem,” said Andrea Garfinkel (’17 PhD Plant Path.)

Garfinkel is helping farmers put a stop to this pervasive pest. Working with growers and scientists in the United States and Europe, she has discovered multiple new species of Botrytis, including one new species that affects grapes and peonies. She also found five other fungal diseases that had never been reported in the United States before.

“Additional knowledge about diseases that impact peonies, such as Botrytis, allows for more efficient and effective use of costly sprays, while ensuring bigger, healthier peony crops,” Garfinkel says. “That’s a win for both peony farmers and consumers.”

She worked with Patricia Holloway, emeritus horticulture professor at the University of Alaska-Fairbanks, and Gary Chastagner, professor at WSU Puyallup, on the multistate project.

Read more about Garfinkel’s work with fungus-affected flowers (Story by Seth Truscott, CAHNRS)

 

Fungal diseases in the soil and on the plants

Wheat and small grains, staples of Pacific Northwest agriculture, have plenty of fungal enemies.

From stripe rust on foliage to root rot underground, WSU researchers have spent many years assisting grain farmers in the ongoing battle against fungi that can destroy or reduce crops.

Stripe rust alone takes a heavy economic toll. Treating infected crops with fungicide is expensive—but if not treated in time, it can cause up to 80 percent crop loss for wheat, the world’s third largest crop.

To make matters worse, it frequently mutates. There’s no way to tell how long any wheat variety will maintain its disease resistance.

That uncertainty is what keeps WSU Professor Arron Carter’s winter wheat breeding program hopping. There are about 80 known stripe-rust resistance genes, and WSU’s plant breeders and crop scientists are constantly looking for new genetic combinations to keep ahead of the evolving threat.

“Disease resistance could only last one year, or it could last fifteen or twenty years,” says Carter ’09. “We’re always looking to breed new varieties that have multiple resistant traits. When we can pyramid resistance genes on top of each other, we have better results.”

Read more about WSU stripe rust research in the Spring 2019 issue.

 

Learn more

It’s fungi to the rescue: The better aspects of fungi helping save the bees, growing plants, and making stock for biofuel (Winter 2022)

Pink snow mold destruction discovered in area wheat fields (WSU News, March 28, 2017)

Wildfire Smoke May Carry Deadly Fungi Long Distances (Wired, Oct. 10, 2022)